Conventional friction clutch assemblies for automotive and other vehicles generally consist of a hub and integral flat clutch driven plate carrying suitable friction surfaces in the form of annular flat friction rings riveted or otherwise secured to the clutch plate. The plate and hub are positioned on a transmission input shaft between a flywheel and reciprocable pressure plate driven by the vehicle motor. When the vehicle operator depresses the clutch pedal, the pressure plate is axially moved away from the flywheel to disengage the clutch and, upon release of the pedal, the pressure plate moves toward the clutch plate which is engaged between the pressure plate and flywheel.
When the clutch is being engaged, the entire contact area of the opposite clutch surfaces substantially simultaneously engages the flywheel and pressure plate, and the clutch may chatter due to the aggressive, grabby nature of the friction material; especially if a metallic friction material is utilized. Chatter is generated when the capacity of an engagement point of the clutch matches the torque demand. At this time the relative motion between the clutching parts is zero, and the friction material assumes its higher static coefficient of friction to stop and hold on the engaging surfaces until the torque demand exceeds this capacity to cause the friction pads to break loose again into a dynamic condition. This jerky stopping and starting of the friction material is chatter. The present invention provides a clutch plate structure obviating the aggressive nature of the friction material.